Optical signal acquisition and processing methods can be useful in medical as well as industrial applications. For example, light signals can be used in some instances to penetrate a range of subsurfaces of a target material. The scattered light reflected from the target material can be used to generate micrometer resolution of three or two-dimensional images that are descriptive of the subsurfaces of the target material. In medical applications, these images can assist a physician to diagnose abnormalities in biological materials. In industrial applications, such images can provide engineers or other specialists insight into the subsurfaces of non-biological materials.